1. Technical Field
The present invention relates to a data managing method, and particularly relates to a dada managing method for a rewritable non-volatile memory, and a memory control circuit unit and a memory storage apparatus using the method.
2. Related Art
In recent years, digital cameras, mobile phones and MP3 players are quickly developed, and consumer's demand on storage media is also increased rapidly. Since a rewritable non-volatile memory module (for example, a flash memory) has characteristics of non-volatile, power-saving, small volume and none mechanical structure, etc., it is adapted to be built in the above various portable multimedia devices.
Along with progress of manufacturing process and cost reduction, memory storage capacity is greatly increased, though data reliability is decreased, and an error correcting code is used to improve the data reliability. Generally, when data is written into the rewritable non-volatile memory module, the data is encoded by an error checking and correcting circuit to generate a corresponding error correcting code. A corresponding decoding procedure is performed to the data read from the rewritable non-volatile memory module, so as to correct an error bit in the read data by using the error correcting code. Conventionally, the error correcting code applied to a NAND flash memory is generated according to a Bose-Chaudhuri-hocquenghem (BCH) algorithm. However, along with increase of the memory capacity, a total time required for correctly decoding data is accordingly increased. Therefore, how to decrease the time required for decoding data to improve decoding efficiency is an important issue concerned by technicians of the field.
Nothing herein should be construed as an admission of knowledge in the prior art of any portion of the present invention. Furthermore, citation or identification of any document in this application is not an admission that such document is available as prior art to the present invention, or that any reference forms a part of the common general knowledge in the art.